GB344592A - Process for the production of 1.1.2-trichlorethane - Google Patents

Abstract

1.1.2-trichlorethane is obtained by causing a mixture of p acetylene, chlorine, and hydrogen chloride to react, risk of explosion being obviated by carrying out the reaction either in narrow or constricted spaces or in the presence of an adequate excess of acetylene or hydrogen chloride or foreign inert gases such as nitrogen or carbon dioxide. Contact materials such as coke, chamotte, quartz, clay, rock salt, active carbon, silica, or pumice, impregnated or not with metallic salts such as mercuric chloride may be present. The process may be carried out in apparatus such as that described in Specification 16620/12, [Class 2 (iii), Dyes &c.], for the production of dichlorethylene. When the initial gaseous mixture is explosive it is caused to react in a vessel filled with material such as coke breeze or sand heated, for example, to 200-250 DEG C. Non-explosive mixtures are heated in the presence of contact materials to temperatures of, for example, 80-150 DEG C. The process may be made cyclic by returning the reaction mixture, after it has passed through a cooler or washer in which the trichlorethane is separated, into the reaction chamber with the addition of fresh chlorine and hydrogen chloride, acetylene being also introduced at another point. A suitable small proportion of the circulating gas may previously be removed in order to diminish the content of foreign gases in the stream, or the circulating gas may be allowed to escape unregulated through a liquid seal. It is desirable to increase the gas velocity locally at the point where the chlorine is introduced. Examples are given. Small amounts of dichlorethylene, acetylene tetrachloride, and ethylidene dichloride are obtained as by-products.